Suspension systems for vehicles include suspension systems that are provided with shock absorbers, corresponding to respective wheels, each shock absorber having a damping coefficient modification mechanism that modifies a damping coefficient that serves as a reference of a damping force exerted on an approach and separation movement of a sprung section and an unsprung section. For instance, the system disclosed in Patent Document 1 is a suspension system wherein respective hydraulic-type shock absorbers, the damping coefficient of which can be modified by exerting resistance against the circulation of a working fluid accompanying sliding of a piston within a housing, and by modifying the exerted resistance, are provided in each of four wheels. In recent years, suspension systems have been studied in which damping coefficients can be modified through enabling control of a damping force by providing, in respective wheels, electromagnetic-type shock absorbers being devices that, relying on the force generated by an electromagnetic motor, generate a force that is exerted on a sprung section and an unsprung section, in a direction in which the sprung section and the unsprung section move closer to or apart from each other.    Patent Document 1: Japanese Patent Application Publication No. 2009-274644